Just for fun, are there any die-hard audiophiles out there that have tested and experimented with underwater worldizing?

I was clacking together large rocks at the bottom of the ocean a while back and thought the echo it created down there sounded pretty cool and wondered if it was possible to experiment with some underwater speakers and mics to create some nifty SFX via water instead of air.

It seems to me that something like this could possibly yield some great results, but it could also be a large waste of time. Has anyone heard of anyone doing something like this before?

What sort of frequency range does a submerged mic pick up?

Could be a fun summer project of mine. I could imagine an elephant roar might sound pretty cool if it's sent via water... Or some sub harmonic info if it's possible... Or it could sound just plain lame. That's why I'm asking - I have no experience with underwater speakers or what is possible to recreate frequency-wise underwater. Has anyone got any experience or info with recording underwater?

Haha! But seriously I like your idea of getting an IR, but that's why I asked about how low you can get frequency-wise - because every hotel I have ever been to that has music in their pool sounds really tinny and thin and NO bass. I wonder if it's a physics thing that you can't get low-end in water.
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UtopiaJan 9 '12 at 2:23

3 Answers
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Willem van den Bos has written a very interesting thesis on the subject. Check the link below. It seems that it is possible, and has been done but there are many factors that make it difficult to achieve. Cost (underwater speakers are expensive) and surface noise (which affect the results) seem to be the most significant.

Very interesting subject. I worked for a year as a sound tech on 'The House of Dancing Water' by Franco Dragone (theatre show on water) which incorporated 36 underwater speakers carrying show-feed and show-call for divers who move props and performers around. I wish I had thought of your worldizing experiment at the time! The underwater system was not part of my jurisdiction but I did dive a couple of times and seem to remember there was no problem with the bottom end, even though the speakers were pretty small (http://www.lubell.com/3400.html). I did do a bit of recording of the system in the pool and the result was nothing like you often get with a 'designed' underwater sound. If it's realism you're after I would recommend worldizing, but you'd probably have to jazz it up a bit after to make it interesting for the listener!
You could try contacting one of those shows (there's one in Vegas as well), they might let you use the system for free if you have the right approach, or for minimal costs. I don't see why not if you only want to play a bunch of sounds and record with a hydrophone or two (stereo is kind of irrelevant as sound travels that much faster but you might get some interesting results with the mics more than 15m apart).
Good luck.

I don't think LF has a problem propagating underwater. It has been used rather effectively as a communications medium (see ELF radio) and LF acoustic sound can travel very long distances under water (see "The Bloop").

Underwater speakers are band-limited, probably for intelligibility reasons. You might also need to be concerned with standing waves if you are in a pool. You can pop an eardrum with enough of a pressure differential.